Properties of PVA tissue phantoms produced by directional solidification.

摘要

Polyvinyl alcohol (PVA) cryogel samples prepared by repeated directional freezing and thawing steps are shown to display an anisotropic structure due to the effect of ice templating during the freezing process. The mechanical stability of the material is improved by the application of a number of directional freeze steps followed by thawing. The anisotropy of the material is confirmed by measurements of acoustic impedance and a simple model is proposed to explain the variation of impedance with the microstructure